Check Bad Lifter In Car???
10-23-2011, 06:29 PM
#1
Burning Brakes
Thread Starter
Check Bad Lifter In Car???
Is there a way to check if a lifter is bad without removing the head? I just put a new set of LS7 style lifters in my car and I think one of them is not pumping up properly.
10-23-2011, 06:47 PM
#2
Tech Contributor
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Location: Anthony TX
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CI 6,7,8,9,11 Vet
St. Jude Donor '08
If I remember correctly,, if you pull the manifold off and remove the valve valley cover,,, you may be able to see some of them.
10-23-2011, 06:56 PM
#3
Drifting
10-23-2011, 07:02 PM
#4
Burning Brakes
Thread Starter
Ok, so what am I looking for then?
Why would a lifter be bad in the first place? What would fail so that it wouldn't work properly? It's a brand new set of lifters riding on a brand new cam, so I'm not worried that the roller is bad... if anything I would think its the hydraulics in the lifter?
I don't know. What's happening is there's a tapping from the engine. The drivers side rocker cover is quiet, but the pass side rocker cover is emitting a tapping when the engine is reved to ~1300 rpm. I just pulled the rocker cover and everything looks ok and the rocker bolts are all tight. This makes me think a lifter isn't working properly?
I thought I read somewhere that the internal spring could go bad and pushing on the pushrods could determine that, but I don't remember where I read that or what the failure mode was and how to be sure?
Why would a lifter be bad in the first place? What would fail so that it wouldn't work properly? It's a brand new set of lifters riding on a brand new cam, so I'm not worried that the roller is bad... if anything I would think its the hydraulics in the lifter?
I don't know. What's happening is there's a tapping from the engine. The drivers side rocker cover is quiet, but the pass side rocker cover is emitting a tapping when the engine is reved to ~1300 rpm. I just pulled the rocker cover and everything looks ok and the rocker bolts are all tight. This makes me think a lifter isn't working properly?
I thought I read somewhere that the internal spring could go bad and pushing on the pushrods could determine that, but I don't remember where I read that or what the failure mode was and how to be sure?
10-23-2011, 07:05 PM
#5
Burning Brakes
Thread Starter
10-23-2011, 07:10 PM
#6
Drifting
10-23-2011, 07:26 PM
#7
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St. Jude Donor '08
There are plenty of things that you will need to check:
1- Use a mechanics stethoscope and it will help you zero in on the exact lifter/rocker. You can even zero in on it on the outside of the valve cover.
Move the metal listening rod over each lifter area. When you figure out what cylinder is noisy, remove the cover and check the rocker trunnion, push rod, spring, and retainer. When the rocker is removed, use the push rod and press down on the lifter and see if it properly pumped up. If it collapses, you found your issue.
There are several types of stethoscopes. I have the metal rod type and a doctors scope with a megaphone on it that i can select with a switch.
Hope this helps
1- Use a mechanics stethoscope and it will help you zero in on the exact lifter/rocker. You can even zero in on it on the outside of the valve cover.
Move the metal listening rod over each lifter area. When you figure out what cylinder is noisy, remove the cover and check the rocker trunnion, push rod, spring, and retainer. When the rocker is removed, use the push rod and press down on the lifter and see if it properly pumped up. If it collapses, you found your issue.
There are several types of stethoscopes. I have the metal rod type and a doctors scope with a megaphone on it that i can select with a switch.
Hope this helps
10-23-2011, 07:59 PM
#8
Burning Brakes
Thread Starter
Yes, I used a stethoscope and narrowed it down to the number 2 or 4 cylinder by listening through the rocker cover. Oddly enough, listening through the cylinder head (between the rocker cover and intake manifold) doesn't reveal much noise at all.
I will pull the rocker cover back off and see what I find.
Question: Even if the spring in a lifter was bad or the check valve was malfunctioning, wouldn't the lifter still pump up with the engine running? I guess I need to research how a hydraulic lifter works...
I will pull the rocker cover back off and see what I find.
Question: Even if the spring in a lifter was bad or the check valve was malfunctioning, wouldn't the lifter still pump up with the engine running? I guess I need to research how a hydraulic lifter works...
10-23-2011, 08:09 PM
#9
Drifting
Insufficient lifter pre-load will increase the propensity for the lifter to bleed down when the engine is off. Sediment on the ckeck valve seat can keep the lifter from pumping up. I always clean new lifters with a solvent, dry them and then soak them in motor oil for several hours prior to installation. I've never had a problem with one failing to pump up.
How much pre-load do you have with this new cam, did you check the wipe pattern and determine pre-load? If the lifter has truly collapsed, there will be no tension on the rocker when cam is a base circle and the valve for the lifter in question is closed.
How much pre-load do you have with this new cam, did you check the wipe pattern and determine pre-load? If the lifter has truly collapsed, there will be no tension on the rocker when cam is a base circle and the valve for the lifter in question is closed.
10-23-2011, 08:57 PM
#10
Burning Brakes
Thread Starter
Just did a little light reading...
I guess that could be it, the check ball not sealing properly? It would have to be bleeding down almost immediately to tap while running, though?
I guess the only way to check which lifter it is would be to assume the one with the bad check ball would be bled down while all the rest would not be possible to compress.
I did not clean the lifters before installing them, but I did soak them in oil. When you clean them do you disassemble them first?
I guess that could be it, the check ball not sealing properly? It would have to be bleeding down almost immediately to tap while running, though?
I guess the only way to check which lifter it is would be to assume the one with the bad check ball would be bled down while all the rest would not be possible to compress.
I did not clean the lifters before installing them, but I did soak them in oil. When you clean them do you disassemble them first?
10-24-2011, 05:19 AM
#11
Drifting
Just did a little light reading...
I guess that could be it, the check ball not sealing properly? It would have to be bleeding down almost immediately to tap while running, though?
I guess the only way to check which lifter it is would be to assume the one with the bad check ball would be bled down while all the rest would not be possible to compress.
I did not clean the lifters before installing them, but I did soak them in oil. When you clean them do you disassemble them first?
I guess that could be it, the check ball not sealing properly? It would have to be bleeding down almost immediately to tap while running, though?
I guess the only way to check which lifter it is would be to assume the one with the bad check ball would be bled down while all the rest would not be possible to compress.
I did not clean the lifters before installing them, but I did soak them in oil. When you clean them do you disassemble them first?
If the lifter is not pumping up, it will not deliver oil to the rocker arm via the push rod while in operation.
10-24-2011, 08:09 AM
#13
Burning Brakes
Thread Starter
Stock rockers with Comp trunion upgrade, PAC 1518 springs, Comp Hi-tec 7.425" pushrods, new LS7 style lifters, LPE GT11 cam. Everything is new as of my recent rebuild, except the rocker bodies and valve springs.
FWIW, when removing the rocker cover all the rockers apear to be covered in oil the same way (oil pooled up in pockets on rocker body, rocker hex bolt head full of oil).
If it is a check valve in one lifter that's not working properly, what's the tapping noise? Is it the plunger bottoming out in the rocker body?
FWIW, when removing the rocker cover all the rockers apear to be covered in oil the same way (oil pooled up in pockets on rocker body, rocker hex bolt head full of oil).
If it is a check valve in one lifter that's not working properly, what's the tapping noise? Is it the plunger bottoming out in the rocker body?
10-24-2011, 09:48 AM
#15
Burning Brakes
Thread Starter
Yep, hence the longer 7.425" pushrods (.040" longer) to keep lifter preload in check (base circle is about .045" smaller radius). Heads are stock with stock valves.
The driver's side is smooth and quiet, the pass side has one obvious "tap-tap-tap" that's barely audible at idle but really speaks up around 1200 RPM.
The driver's side is smooth and quiet, the pass side has one obvious "tap-tap-tap" that's barely audible at idle but really speaks up around 1200 RPM.
10-24-2011, 12:24 PM
#16
Team Owner
If the valve cover is off, you might want to check for contact in the areas of concern. Also, are you sure its not an injector as they can be quite noisy at times as well.
10-24-2011, 01:11 PM
#17
Burning Brakes
Thread Starter
LOL - Injectors. Yes, my injectors are quite loud and I've been probing and scoping all over the place looking for taps and ticks.
At first I was convinced this noise was in injector radiating sound up into the injector rail. I ruled that out by running the car without the steel clips that hold the injector to the rail (I used an extra set of o-rings in the intake manifold for the injectors to press against - keeping them safely in the rail). That quieted down the fuel rails considerably but I was still left with a "tap".
I was previously listening to the heads (with a stethoscope) on the flat surface where the intake ports are, right beside the intake manifold. Listening to the heads on this surface reveals nothing but quiet, smooth clomping from the valvetrain.
Then I tried listening though the rocker covers - it didn't even sound like the same engine! MUCH more valvetrain noise is apparent through the covers. Even still, the driver's side cover sounds fine; clomping valves, light "ringing", but nothing harsh sounding. The pass side cover is another story, with a very distinct "tap-tap-tap" coming from the #4 or #2 cylinder area.
Listening to the block in front of the pass side cylinder head (right behind the water pump) reveals almost no noise at all... nice and smooth. It's amazing how much noise one area of an engine can make while another area remains extremely quiet. I had assumed that, being large chunks of aluminum bolted together, a tap or knock would be audible everywhere. That doesn't seem to be the case, which is pretty handy for tracking down a problem.
At first I was convinced this noise was in injector radiating sound up into the injector rail. I ruled that out by running the car without the steel clips that hold the injector to the rail (I used an extra set of o-rings in the intake manifold for the injectors to press against - keeping them safely in the rail). That quieted down the fuel rails considerably but I was still left with a "tap".
I was previously listening to the heads (with a stethoscope) on the flat surface where the intake ports are, right beside the intake manifold. Listening to the heads on this surface reveals nothing but quiet, smooth clomping from the valvetrain.
Then I tried listening though the rocker covers - it didn't even sound like the same engine! MUCH more valvetrain noise is apparent through the covers. Even still, the driver's side cover sounds fine; clomping valves, light "ringing", but nothing harsh sounding. The pass side cover is another story, with a very distinct "tap-tap-tap" coming from the #4 or #2 cylinder area.
Listening to the block in front of the pass side cylinder head (right behind the water pump) reveals almost no noise at all... nice and smooth. It's amazing how much noise one area of an engine can make while another area remains extremely quiet. I had assumed that, being large chunks of aluminum bolted together, a tap or knock would be audible everywhere. That doesn't seem to be the case, which is pretty handy for tracking down a problem.
10-24-2011, 01:18 PM
#18
Tech Contributor
LOL - Injectors. Yes, my injectors are quite loud and I've been probing and scoping all over the place looking for taps and ticks.
At first I was convinced this noise was in injector radiating sound up into the injector rail. I ruled that out by running the car without the steel clips that hold the injector to the rail (I used an extra set of o-rings in the intake manifold for the injectors to press against - keeping them safely in the rail). That quieted down the fuel rails considerably but I was still left with a "tap".
I was previously listening to the heads (with a stethoscope) on the flat surface where the intake ports are, right beside the intake manifold. Listening to the heads on this surface reveals nothing but quiet, smooth clomping from the valvetrain.
Then I tried listening though the rocker covers - it didn't even sound like the same engine! MUCH more valvetrain noise is apparent through the covers. Even still, the driver's side cover sounds fine; clomping valves, light "ringing", but nothing harsh sounding. The pass side cover is another story, with a very distinct "tap-tap-tap" coming from the #4 or #2 cylinder area.
Listening to the block in front of the pass side cylinder head (right behind the water pump) reveals almost no noise at all... nice and smooth. It's amazing how much noise one area of an engine can make while another area remains extremely quiet. I had assumed that, being large chunks of aluminum bolted together, a tap or knock would be audible everywhere. That doesn't seem to be the case, which is pretty handy for tracking down a problem.
At first I was convinced this noise was in injector radiating sound up into the injector rail. I ruled that out by running the car without the steel clips that hold the injector to the rail (I used an extra set of o-rings in the intake manifold for the injectors to press against - keeping them safely in the rail). That quieted down the fuel rails considerably but I was still left with a "tap".
I was previously listening to the heads (with a stethoscope) on the flat surface where the intake ports are, right beside the intake manifold. Listening to the heads on this surface reveals nothing but quiet, smooth clomping from the valvetrain.
Then I tried listening though the rocker covers - it didn't even sound like the same engine! MUCH more valvetrain noise is apparent through the covers. Even still, the driver's side cover sounds fine; clomping valves, light "ringing", but nothing harsh sounding. The pass side cover is another story, with a very distinct "tap-tap-tap" coming from the #4 or #2 cylinder area.
Listening to the block in front of the pass side cylinder head (right behind the water pump) reveals almost no noise at all... nice and smooth. It's amazing how much noise one area of an engine can make while another area remains extremely quiet. I had assumed that, being large chunks of aluminum bolted together, a tap or knock would be audible everywhere. That doesn't seem to be the case, which is pretty handy for tracking down a problem.
10-24-2011, 01:55 PM
#19
Drifting
LOL - Injectors. Yes, my injectors are quite loud and I've been probing and scoping all over the place looking for taps and ticks.
At first I was convinced this noise was in injector radiating sound up into the injector rail. I ruled that out by running the car without the steel clips that hold the injector to the rail (I used an extra set of o-rings in the intake manifold for the injectors to press against - keeping them safely in the rail). That quieted down the fuel rails considerably but I was still left with a "tap".
I was previously listening to the heads (with a stethoscope) on the flat surface where the intake ports are, right beside the intake manifold. Listening to the heads on this surface reveals nothing but quiet, smooth clomping from the valvetrain.
Then I tried listening though the rocker covers - it didn't even sound like the same engine! MUCH more valvetrain noise is apparent through the covers. Even still, the driver's side cover sounds fine; clomping valves, light "ringing", but nothing harsh sounding. The pass side cover is another story, with a very distinct "tap-tap-tap" coming from the #4 or #2 cylinder area.
Listening to the block in front of the pass side cylinder head (right behind the water pump) reveals almost no noise at all... nice and smooth. It's amazing how much noise one area of an engine can make while another area remains extremely quiet. I had assumed that, being large chunks of aluminum bolted together, a tap or knock would be audible everywhere. That doesn't seem to be the case, which is pretty handy for tracking down a problem.
At first I was convinced this noise was in injector radiating sound up into the injector rail. I ruled that out by running the car without the steel clips that hold the injector to the rail (I used an extra set of o-rings in the intake manifold for the injectors to press against - keeping them safely in the rail). That quieted down the fuel rails considerably but I was still left with a "tap".
I was previously listening to the heads (with a stethoscope) on the flat surface where the intake ports are, right beside the intake manifold. Listening to the heads on this surface reveals nothing but quiet, smooth clomping from the valvetrain.
Then I tried listening though the rocker covers - it didn't even sound like the same engine! MUCH more valvetrain noise is apparent through the covers. Even still, the driver's side cover sounds fine; clomping valves, light "ringing", but nothing harsh sounding. The pass side cover is another story, with a very distinct "tap-tap-tap" coming from the #4 or #2 cylinder area.
Listening to the block in front of the pass side cylinder head (right behind the water pump) reveals almost no noise at all... nice and smooth. It's amazing how much noise one area of an engine can make while another area remains extremely quiet. I had assumed that, being large chunks of aluminum bolted together, a tap or knock would be audible everywhere. That doesn't seem to be the case, which is pretty handy for tracking down a problem.
In my opinion, if you believe you have is narrowed down to a particular cylinder head and location, you need to bite the bullet and run the engine with the valve cover off so you can see what is taking place. Yes it is going to make a mess.
10-24-2011, 02:45 PM
#20
Burning Brakes
Thread Starter
When originally scoping the fuel injectors/rails (set up with retaining clips) and the cylinder head (on the intake port surface) I was hearing lots of noise from the injectors/rails and NONE from the head.
Now with the fuel rails/injectors ruled out (rubber isolation) and measuring from the ROCKER COVER instead of directly off the head, it is obvious that the noise I'm hearing is coming from the valvetrain.
Scoping the head on the intake port side still reveals no noise. The revelation here was scoping the rocker cover instead of the head. There are no coil pack bolts loose that could cause a rattle on the cover itself.
Injectors are still noisy, but that's RELATIVELY noisy, and they all sound about the same. No one injector sounds significantly louder than the rest.
EDIT: I still believe I have a fuel rail noise issue, but that investigation will be waiting until the spring. For now I'm just going to try to nail down this lifter problem.
Last edited by Blue Angel; 10-24-2011 at 02:56 PM.